Pat Freeman
Well-Known Member
After installing Todd Z's Throttle Body on my '07 V8, I have run both the stock 87 octane tune and the Xcal2 93 octane tune to do a comparison test. I ran quite a few tanks of 87 before running 3 tanks of 93 to make this comparison over the past few weeks. Unfortunately, I have no access to a dyno, nor did I want to spend the money trying to provide such accurate results.
The test that I have been doing is to see how fast I can get my ST between a stop sign and a speed limit sign on the way home from work. I did this test every day by ensuring there was no traffic around, that the road surface was dry and that I wouldn't impact anyone/anything. I do not know the exact distance to the speed limit sign from the stop sign. That's not important to me. What was important was that I was actually seeing a difference between unmodded TB 87, modded TB 87 and modded TB 93. My truck is stock except for the Magnaflow exhaust. Here goes...
Unmodded TB 87. I was able to accellerate from stop to speed limit sign a few hundred feet away and reach 55MPH. The truck took a little while to "get up and go" as response time was a little weak, something we all experience and some blame this on the throttle by wire. 14MPG city, 17MPG highway.
Modded TB 87. I was able to get to 60MPH. As reported on this forum previously, the initial responsiveness and power was significantly increased running the stock tune from the factory with Todd's TB modification. His mod doesn't make the transmission shift any better like the Xcal2, but there is better response from the engine and there is more power you can feel in the seat-of-the-pants. 15MPG city, 19MPG highway.
Modded TB 93. I was able to get between 60 and 65MPH. Shifts are much firmer and ST wants to plant you farther into the seat as RPMs increase. VERY nice performance combination! Although, from what I remember, it doesn't feel much different than the 93 octane tune on the unmodded TB. I would have to remove the TB and test with 93 but I don't want to. 14MPG city, 18MPG highway.
I have recently switched back to the stock 87 tune on 87 fuel and I actually miss the performance I was getting from the combination TB / 93. I just don't want to pay a lot for this fuel.
None of my measurements are accurate. It was just a seat of the pants test with me glancing at the speedometer. However, it is at least some data for those that are considering multiple mods. I'm going to stay on 87 octane for now. But, I really miss the 93 octane with Todd's TB mod!
The test that I have been doing is to see how fast I can get my ST between a stop sign and a speed limit sign on the way home from work. I did this test every day by ensuring there was no traffic around, that the road surface was dry and that I wouldn't impact anyone/anything. I do not know the exact distance to the speed limit sign from the stop sign. That's not important to me. What was important was that I was actually seeing a difference between unmodded TB 87, modded TB 87 and modded TB 93. My truck is stock except for the Magnaflow exhaust. Here goes...
Unmodded TB 87. I was able to accellerate from stop to speed limit sign a few hundred feet away and reach 55MPH. The truck took a little while to "get up and go" as response time was a little weak, something we all experience and some blame this on the throttle by wire. 14MPG city, 17MPG highway.
Modded TB 87. I was able to get to 60MPH. As reported on this forum previously, the initial responsiveness and power was significantly increased running the stock tune from the factory with Todd's TB modification. His mod doesn't make the transmission shift any better like the Xcal2, but there is better response from the engine and there is more power you can feel in the seat-of-the-pants. 15MPG city, 19MPG highway.
Modded TB 93. I was able to get between 60 and 65MPH. Shifts are much firmer and ST wants to plant you farther into the seat as RPMs increase. VERY nice performance combination! Although, from what I remember, it doesn't feel much different than the 93 octane tune on the unmodded TB. I would have to remove the TB and test with 93 but I don't want to. 14MPG city, 18MPG highway.
I have recently switched back to the stock 87 tune on 87 fuel and I actually miss the performance I was getting from the combination TB / 93. I just don't want to pay a lot for this fuel.
None of my measurements are accurate. It was just a seat of the pants test with me glancing at the speedometer. However, it is at least some data for those that are considering multiple mods. I'm going to stay on 87 octane for now. But, I really miss the 93 octane with Todd's TB mod!
